T.cursor( x i : C i ,… )

Read(880) Label: cursor, pseudo table,

Description:

Get a cursor based on a pseudo table object.

Syntax:

T.cursor(xi:Ci,…)

Note:

The function gets a cursor based on pseudo table T by specifying field expressions xi and field names Ci, which, by default, field names in the pseudo table. It gets a cursor using all fields of the pseudo table when paramters xi:Ci are absent.

 

Only supported by esProc Enterprise Edition.

Parameter:

T

A pseudo table.

xi

A field expression.

Ci

Field name in a result table sequence.

 

Return value:

Cursor

Example:

 

A

 

1

=create(file).record(["D:/file/pseudo/empT.ctx"])

 

2

=pseudo(A1)

Generate a pseudo table object.

3

=A2.cursor()

Generate a cursor from A2’s pseudo table using all its fields, since no parameters are present.

4

=A3.fetch()

Below is data in A3’s cursor:

5

=A2.cursor(EID:eid,NAME,SALARY:salary)

Retrieve fields EID, NAME and SALARY from the pseudo table to generate a cursor with new field names eid, NAME and salary respectively.

6

=A5.fetch()

Below is data in A5’s cursor:

 

mcs.cursor(n)

Description:

Merge subcursors in a multicursor into a unicursor or a new multicursor with a smaller number of parallel subcursors.

Syntax:

mcs.cursor(n)

Note:

The function merges subcursors in a multicursor into a unicursor, which is the default, or a new multicursor with a smaller number, which is specified by parameter n, of parallel subcursors.

Parameter:

mcs

A multicursor.

n

Subcursor column name.

Return value:

Cursor/Multicursor

Example:

 

A

 

1

=demo.query("select * from EMPLOYEE").cursor@m(5)

Return a multicursor having 5 subcursors.

2

=A1.cursor(3)

Merge subcursors in the multicursor and convert it to a 3-subcursor multicursor.

3

=A2.cursor()

Convert a multicursor to a unicursor.